A gunman killed himself Thursday after shooting his boss in the Bank of America building in Chicago's financial district, authorities said.

The victim was Steven LaVoie, the CEO of ArrowStream, which the suspect also worked for, the company said. The suspect, identified as Tony DeFrances by the Chicago Medical Examiner’s Office, had been demoted last Friday, police said.

"We are deeply saddened and shocked by the events that have occurred today," ArrowStream said in a statement. "Our focus during this tragedy is to ensure the well being of our ArrowStream family. We want to assure our customers that our business continuity plan is in place, and our operations will continue to function normally."

"Thank you to our family and friends for your outpouring of love and support. Our thoughts are also with Steven's extended family, the employees of ArrowStream, who mean so much to Steven," read a statement from LaVoie's family.

LaVoie, who police said was 54, was taken to Northwestern University Hospital and was in critical condition after suffering a gunshot wound to the head.

The 59-year-old shooter, later identified as DeFrances, was confirmed dead at the scene, police said.

Police were alerted to the shooting at 9:50 a.m. local time.

The shooting took place on the 17th floor of the building at 231 South LaSalle Street, police and ArrowStream said.

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